Vulcanizer



p 8, 1943. HT. TORNBERG 2,330,319

VULCANI ZER Filed March 14, 1941 7 Sheets-Sheet 1 iiiiiiifl Sept. 28,1943.

' H. T. TORNBERG VULCANIZER Filed March 14, 1941 Y 7 Sheets-Shet 2III/III N A IIIVIIIIIIIIII'II.

p 28, 1943. H. T. TQRNBERG 2,330,319

VULOANIZER Filed March 14, 1941 '7 Sheets-Sheet 3 I INVENTOR. Hem/m4- T.Tam/am Sept. 28, 1943.

H. T. TORNBERG VULCANIZER Filed March 14, 1941 7 Sheets-Sheet 5 Sept.28, 1943. H. 'r. TORNBERG VULCANI ZER Filed March 14, 1941 7Sheets-Sheet 6 Illl Sept. 28, 1943.

H. T. TORNBERG VULCANIZER I Filed March 14, 1941 '7 Sheets-Sheet IN VENTOR.

- "WWW Patented Sept. 28, 1943 Henning T. Tornberg,

National. Rubber Machinery Akron, Ohio, assignor to a corporation ofOhio Application March 14,1941, Serial No. 383,315

2 Claims. (01.18-1'7) This invention relates to vulcanizing presses, andin particular relates to vulcanizing presses for manufacturing hardrubber or like articles, such as vehicle steering wheels;

In the manufacture ofhard rubber articles of the character described,certain volatile pigments used in the rubber generate gases in the heatof vulcanization. If these gasesare not expelled from between the moldsections o'fJ-the press before they are fully closed for the curingcycle, gas pockets in the mold cavities will ause the articles to benon-uniform in shape, orformed with imperfections, such as fiat portionsor depressions. I I V I In the past, expansible diaphragm or bags ofknown type have been used to apply a final squeeze pressurebetween'registering mold'sec;

tio-ns upon/closing a vulcanizing press, to allow.

for slack in the press operating mechanism and insure full engagement ofthe contacting surfaces of said registering sections. Sucli diaphragms,however. have been limited as to the pressure obtainable, and as to theamount of slackfwhich may be taken up; 'I-Iydraulic' ramsfor thispurpose also have been objectionable in 'the past, becauseno'satisfactory mean hasbeen devised prior to the present invention forpreventing loss of pressure fluid, such as oil, from between therelativelymovable parts of the ram. I

An object of the invention is to provide 3 an improved press of thecharacter described'includ I ing mating mold sectionsand mean forrelatively'movihg the sections toward substantially mating relation, thepress having yielding, selfcentering means for applying article-formingpressure between the mating mold sections. I

Another object of this invention is to provide a press of the classdescribed having provision for expelling gases from between the matingmold sections thereof, prior to the curing cycle, where by, articlesformed in the mold, cavities will be of uniform shape, and wherebyimperfections caused by gas pocketswill be obviated.

Another object of the invention isto provide in a press of the characterdescribed improved means for conveying gases from between the moldsections to prevent escape thereof outwardly of the press. 1 I

Another object of the invention is to provide in a press of theclassdescribed improved ejector means for automatically stripping andejecting the finished product from a; mold cavity thereof, withpower-operated means for operating the ejecting means so that said moldcavity will be free and unobstructed to permit free insertion anautomatically operable inside the outer casin y 00., Akron, Ohio,

therein of a preformed 0r unvulcanized article for a succeedingvulcanizing cycle.

Still another object of the invention is to pro,- vide a press of thecharacter described, including hydraulic. ram for applying thearticle-forming pressure between the mold sections after the press isclosed for-1a vulcanizing cycle, with means provided to recover orprevent loss of pressureofiuid from between relatively movable parts ofthe ram. j I

, These and, other objects of the invention will be manifest from thefollowing brief description and the accompanying drawings. I

Of the accompanying drawings;

Figurefll is affront elevation, partly broken away. and in section, of avulcanizing press em- Figure 2"i s a fragmentar iew, pa rtlybroke n awayandin'se'ction, at'thefront of the press at the lower central portionthereof and'taken limit switches inopen position of the press, Figure3.is a side elevation, partly'brok'en away,

of the press as viewed from the right of Figure l.

"Figure 4 is' an enlarged fragmentary crosssection taken substantiallyon line 4-4 of Figure 1, but with the mold sections shown inintermediate cljosing*positio ns with respect to each other. I

Figure 5" is an enlarged cross section; taken substantiallyon line 55 ofFigure 1.

Figure 6 is an enlarged. fragmentary cross;-

section illustrating the upper portion of the ejector mechanism inassociation with the mold. sections asv iewed inFigure 5. I Figure? i afragmentary cross-section taken on. line '|'-'l of Figure 6.

Figure 8 is a View similar on a reduced scale, illustrating the press infully p np i o i j I Figure!) is an enlarged cross-section takensubstantially on line 99 of Figure 5. I I Figure 10 is a fragmentarycross-section, great- 1y enlarged, taken substantially on line l0 -Iflof Figure 9. I a I Figure 11 is an enlarged cross-sectional View takensubstantially on line l'-ll of'Figure15, illustrating the ejector,operating and latching mechanism. v Figure "12 is an enlargedcross-section taken substantially on line l2-l2 of Figure 8.

Figure 13 is an enlarged fragmentarywiew 'takensubstantially on line13-43 of Figure 12.

Figurelii a schematic wiring diagram illusillustrating the press to IFigure 5, but

I4, carrying upper mold sections I5, I for registering with the lowersection I3 when the head is relatively moved toward said member ID. Thelower sections, broadly speaking, are considered as being relativelyfixed with respect to the general opening and closing movementsof thepress, but are Vertically movable in a manner to be described after thepress head is in closed position.

i he h ad 4 may be moved in Paralle sm from and toward a sed posi ion ot e res i which be e is i faces f th re pectiv m l tie I3 and I5 a e inl h ly s a d r at on. as

wil b later escribed. d fr m and t a rearw rdlv lt posi ion when th pess is opene (s e chain dot ed lines in Figu e .3). For this pu po e, te up e pres m mb r is p v ta v sup o t d on pins L secur n op osite endsthereof, between a pair of side arms I1, I] which at n-downwardl s rad nl wer pr ss m ber 1.0, these. arms being pivotally connected at thelower ends thereof to pins I,8 of crank members l9 which are suitablykeyed. on a shaft journalled in bearings 2I and 22 in uprights II and1;?

I i respectively. The shaft 25 is driven by a pair of gears. 2,3 .234kevedthereon engagingpinions 24, which in turnare driven. through asuitable re.- auc o searing 2.5 by a reversing motor 26.

Means for controlling the angular movements of. head I 5 inthe mannerdescribed is best shown inFi ures 1, 3 and 8. Cam plates ,2] aresuitably secured adjacent opposite ends of movable head I4 inward y ofarms 11, these plates each having a cam slot 28 therein for receivi g apair of spaced rollers 29, 29v which are mounted on a plate 30 fixedlysecured to the lower press member I0. These spaced rollers engage alonga substantial length of the cam-slot 23 to restrain a cam plate 21against relative pivotal movement at any given position of the rollerstherein, except as the cam plate is allowed to. assume various annularpositions, with respect'to fixed, plate 30, determined by thedirectiouof the cam slot. atxvarious. points during theopening and closing of.the press.

In the present instance the cam. slot 23 is shaped and. directed s thatthe head. ll! will move in parallelism from and toward. the closedposition thereof with respect to-the lower press member ID, and so thatas. the head moves toward the fully open position the side arms I! willboner..- m t 0 t lt earward v on he cr n p thereby allowing the head I.4 to tilt rearwardly, as restrained. by the cam plate and the spacedrollers, to permit. fr.ee access to the lower mold cavity (see Figure8).

InteIPQsed between the upper mold section I5 and a bottomwall or plateill of head M may be an electrically heated plate 32 for heating saidmold section, removable and replaceable heat insulating spacer plates 33and 34 being provided between the heating plate and wall 3| of the head.

In order to insure complete registry of the respective pairs of moldsections. when the press is closed by the press-operating mechanism de-Iii scribed above, each lower mold section I3 is mounted on the upperend of a vertically shiftable piston 35 of a hydraulic ram, indicatedgenerally at 35, the ram being automatically operable to applyarticle-forming pressure between the upper and lower mold section afterthe upper press member I4 has moved to closed position. Betweenthepiston 35 and section I3 may be an electricalheating plate 31 imilar toplate 32, and a removable and replaceable, heat-insulating spacer plate38. Piston 35 is vertically slidable in a cylinder 39, the latterincluding a bottom wall and an annular side wall M, this cylinder beingfixedly received in a recess 32 of a cupshaped portion 43 formed in theplaten !2.

Referring particularly to Figures 5 and 10, a hollow stem or rod issuitably fixedly received in a central opening through piston 35, adownward extension 6| of said stem being slidably received through aboreB2 in cylinder bottom plate ll]. Bottom plate. 40 has a boss. 63extending through'an opening in the bottomof cup-shaped portion 43, inwhich boss is a bore for ,a packing gland 64 adjustable by means ofscrews 65, against packing P which may comprise two series of V -shapedpacking rings 66, between end adapter rings 61, 61 and a centralmetallic separator ring58, the purpose of. which will be describedlater'. The packing P is provided to prevent leakage of pressure fluidbetween the cylinder and stem extension .GI.

The top of piston 35 is provided with an annular flange 44, the bottomedge of which is en.- gageable with the-top edge portion of the wall 4|of the cylinder, when the piston is at the bottom of its stroke in thenormal inoperative position thereof. A ring. .46, secured to the top ofplaten I2, i providedwith an annular shoulder portion 41 against whichthe top edge of flange 44 abuts for limiting. upward movement of thepiston. A

suitable annular, self-expanding gasket 48 may be replaceably securedadjacent the bottom of the piston for engagement with the innerperiphery ofv the cylinder, to prevent. leakage of pressure fluidbetween the piston and the-cylinder.

For operating both rams .33 simultaneously, pressure fluid, suchas oil,is supplied to the bottom of cylinder 39 through piping 50,50.connecting a valve 5I,.which is connected by piping 52 to a suitablesource of pressure-fluidsupply (not shown). Valve 5| is controlled bytwo solenoids 53, 5.4 (see Figures 8 and 14) for actuating a lever 55 onthe valve in opposite directions, either to permit passage of fluid tothe cylinder through piping 52. and 5.8 to urge piston 35 of the ramupwardly, Or to return the fluid to the source of supply through piping50 and piping 51 to lower the piston 35. The solenoids 5.3, 54 areactuated F in timed sequence with other operations during the cycle ofoperation of the press, as will be subsequently described in connectionwith wiring diagram. 1

As best. illustrated in chain-dotted lines at H in Figure 8, thearrangement is such that when the press head I4 is in the fully closedposition thereof, but with preformed unvulcanized articles W receivedwithin lower mold cavities and before pressure is applied to the pistons35 of the hydraulic rams, there will be clearance between theregistering faces of the upper and lower mold sections I3 and I5,toallow for the rough oversize of said performed articles, for example.The press may be maintained in this initial closed condition for arelatively short time to preheat and soften the rubber 'andfu'rtherpreform the article, the mold sections! being continuously heatedbymeans of heating plates '32 and 31. After this short preheating periodthe press mo tion .is reversed an amount sufilcient to widen the gapbetween the registering mold sections as shown in Figure4, andimmediately closed again to the first-mentioned'closed position.This'last named closing movement is efiective to force or bump out frombetween the mold sections gases generated by certain chemicals in therubber under the influence'of heat. "Upon closing the press this secondtime pressure fluid may be supplied to the hydraulic ram to urge piston35 upwardly, thereby to apply heavy yielding pressure between the upperand lower mold sections. The piston is maintained in this conditionduring a curing cycle, as controlled by altimer mechanism to bedescribed later, duringwhich cycle the articles are formed undertheinfluence of heat and pressure. At the end .of the curing cycle,valve is automatically actuated by the timer to return thepressure'fluid incylinder 39 to the source of pressure supply, throughpiping 50 and 51.

Because of the high pressure of the oil, or other pressure fluid, inrain 35 thereis a tendency for much of the oil to be forced upwardlybetween the piston 35 and cylinder wall 4| and also downwardly past thestem extension 6|. Oil-recovery means is provided herein to prevent lossof fluid in this mariner, Withcons'equent' economy and efliciency ofoperation. of the apparatus. As shown in Figures 5, 9 and 10, thisrecovery means may comprise an annular groove or chamber 10 in thecylinder wall 4|,adjacent the top thereof, this groove communicatingwith an annular chamber H in the cylinder bottom plate 40, through aplurality ofpassages .12, 12 insaid wall M. Radially extending passages13, 13 communicate chamber H with annular roove 68 in the outerperiphery of separating ring 68 which communicates with a similar groove68* on the inner periphery thereof through a plurality of openings 68."Piping :15 is connected to cylinder bottom plate 49 to communicatechamber H withsaid source of pressure oil supply. Groove 58* isrelatively wide so that it will cooperate with the openings 13 when thepacking gland 65 is 'adiusted. The arrangement is such that oil escapingpast the piston 35 or the stem extension ti thereof will follow paths ofleast resistance, returning to chamber H and thence through piping l5'tothe source of oil supply.

Referring particularly to Figures 4 to 8 of the drawings, means 16- is:provided for centering the green steering wheels W in the lower moldcavity. The centering means 16 may comprise a head portion 11, securedor retained flush with the underside of lower mold section I 3, saidhead having thereon a pin I8 adapted to be received through theusualcentral openinginthe metallic core C about which raw rubber has beenroughly preformed (see Figure 4). Pin 18 is tapered at its free end tobe received in a tapered hole 15 in the upper mold section [5 when themold sections are in full registering relation.

For automatically ejecting the finished product from the lower moldsection during opening of the press, ejector mechanism, indicatedgenerally at 80 (see Figures 4. to- 8), may be provided.

Vertically slidable in the upper portion of a bore 8! in sleeve 60 is apin 82, in the upperend of which are a pair ofprongs 83 83slidablethrough openings which extend through the centering spring HM(see Figures '12 and 13).

means 76 in thefilower'rmold section, to" be engageable' with a-portionofcore C of wheel W when pin orrod 82 is urged upwardly. Ashoulderportion 84 on the upper end of pin 82 .is normally seated ina recess inthe upperend of sleeve or stem 68 .to limit downward movement of saidpin 82. Slidable in the lower portionjof bore 8| in sleeve may bea rod85 the upper endof which is engageable with thelower end of rod 82, andin the lower endof which-are oppositely disposed pins 86, 86. receivedinslots 87-, Bl in the bifurcated end of an arm. 88; which is pivotallymounted at 88 in abracket 98*? o-nhousinglll to swing in a verticalplane. 'A portion of arm 83 r is engageable with the edge portion of acircular cam surface 953 provided on a hub on large driving gear 23,0123*. as thecase .may be (see Figure 1), normally to limit downwardmovement of rod 85 in inoperative position.

For urging therods 85 and 82 upwardly, to eject a finished article Wfrom the lower mold section as the press is opening a cam arm 9| ispivoted on pivot 89'to swing vertically in parallelism with arm 88,thetwo arms being normally locked together by an electrically releasablelatching device, indicated generally at92. The un derside of the freeendof arm 9! is rounded upwardly for normally inoperatively resting orriding on cam surface 9% of gear 23 in latched relation with the arm'88.,The, cam arm 9| is yieldingly maintained in contact with cam surface 90on hub 90 or with cam roller 93'by a spring-pressed pin 9H in a housingM secured on the underside of the cup-shaped portion 43 of platen l2.During the opening movement-of the press, a'cam roller 93 on gear 23 isengageable with cam arm,

9| to urge the latter and arm 38 l'atchedthereto upwardly, arm 88thereby urging rods 85 and 82 upwardly to eject a vulcanized article tothe relative position with respect to th lower mold section shown inchain-dottedlines in-FigureS. In

such position the article is readily removable from the press. g

Thelatching device 92'isbest shown in Figures 5, 8, ll, 12 and,l3. Asuitable cylindrical" housing 95, fixedly received tl irough an openingflange being concave lor dished for guiding the.

latch end 93into the sleeve opening as urged by When the press isoperated toward the closed position shown in Figure 5, for, exa'mplaarin9! will be moved downwardly to a position in which latch portion 98 willbe yieldingly urged into sleeve 99, as described above, to latch or lookarms 91 and 88 together in readiness for an article ejecting operationwhen the press is next operated toward fully open position, at whichtime cam roller 93 urgescam arm 9l' upwardly as previously described. a

In'order properly to position a .green orpreformed article W in thelower. mold section 83 when the press is in-open position, after apreviously finished article has been removed, it is necessary towithdraw the article engaging prongs 83 of ejector rod 82 from the lowermold cavity; For this purpose, between the arm 80 and a flanged portion95- on cylinder 05 may be secured a collar I02 from the lower portion ofwhich extends a pair of laterally spaced lugs I03, between which'a crankI05is pivoted at I04. An upwardly extending bifurcated arm I06 has slotsin the upper ends of the bifurcated portionsfor receiving oppositelydisposed trunnions I01, It! on a block I08, which is retained on areduced extension I09 of latch shaft 9'! by a collar IEO secured on theend of the extension. Extending angularly of arm I on the crank may bean arm II2 the free end of whichis pivotally connected by a. pin H3 inthe bifurcated upper end of a vertically extending rod II4, the lowerend of which is connected to one end of a lever I I which is pivoted toa bracket IIB. The other end of lever II 5 may be connected by a linkII! to the core H3 of a solenoid bracket. The pin H3 is slidable inslots IIEF in said upper end of rod II4 to provide lost motion action-tocrank I05, so that the latch will not be tripped by the upward swingingmovement of arms 83 and 9|. energized by the press operator pressing abutton (not shown) when the press is open as described above to swinglever I I 5 as shown in chain-dotted lines in Figure 11, and through rodI I4 and crank I05 to release latch end 98 from sleeve 99 and therebydisconnect arms 88 and EH. This allows arm 88 and rod 85 to drop bygravity until the arm rests on cam portion 90 of gear 23, which alsoallows ejector rod 82 to drop by gravity to its lowermost position towithdraw engaging prongs S3 thereon to inoperative position (see Figure8). The upper press member or head I4 may be formed with skirt portionsI4, l4, which extend downwardly about the registering mold sections whenthe press is closed, to catch or trap the gases expelled from the mold.By suitable suctime means (not shown) these gases are drawn into achamber or chambers I4 in the head, through openings I 4 in the bottomplate 3| of the head, and outwardly thereof through a suitable exhaustconduit 14 Thus obnoxious gases generated by the vulcanizing process,are prevented from permeating the air about the press to injure the"health of the press operators or otherwise cause discomfort.

The'schematic wiring diagram shown'in Figlll'6'll,Wl11 now be describedin connection with a brief description of the general operation, of thepress.

In the operation of the press, while the press is stopped in the openposition shown in Figure 8, the operator seats a roughly preformed wheelW in the lower mold cavity, with centering pin I9 received through the,central opening of the wheel. In this position of the press the ejectorarms 88 and ill will be disconnected. The operator momentarily presses a"close button on the press, which closes a circuit, through a stopbutton and a transformer I connected across power lines L1, L toenergize a coil I2I which throws closing switches C connected to powerlines L1, L2, L3 to start the press motor 26. This, through pinions 24,drives large gears 23, 23 to turn cranks I9 in clockwise direction (seechaindotted lines in Figure 3) whereby the side arms I! carry the presshead I4 toward the closedposition thereof shown in full lines in Figure3, the cam plates 21 on opposite ends of head I4 and the pairs ofrollers 29 onthe fixed lower press member ID engaging inthe cam slots 28causing II9 mounted on said The solenoid is electrically circuit fromtransformer the head to move in' parallelism toward an initial orintermediate closed position of the press, in which arms H are on deadcenter and the registering faces of the upper and lower mold sectionsare in slightly spaced relation to allow for oversize of the preformedwheel W in the lower mold cavity (see also chain-dotted position of moldsection I 5 in Figure 8). In this position of the press the piston ofthe hydraulic ram 35 remains in the down position shown in Figure 8.

In the meantime, the operator having momentarily pressedthe close button(Figure 14) a secondary press-closing circuit was established throughnormally closed contacts a-b of press limit switch LS1 (Figure 2) by thecoil I2I operating aholding relay 1-10, the purpose of which is to holdswitches,C closed to keep motor 23 running after the close" button isreleased. The contacts ab of LS1 are open only when the press is stoppedin closed position.

When the press has operated to the initial closed position describedabove (Figure 3) a cam I22 on driven gear 23. will operate switch L8; toopen contacts a'--b, de-energizing coil I2I and holding relay BC to stopthe press operating motor 25, but at the same time closing a timer I20,across contacts (1-0 of LS1 to start a timer motor T, which, by means ofcams C1, C2, C3, C4, and C5 operating a series of switches S1, S2, S3,S4 and S5, respectively, starts a series of article-forming opera tionsof the press. The timer mechanism may be of suitable type readilyobtainable on the market.

All of these timer operated switches are normally closed except'switchS2. First, cam Ca momentarily closes switch $3, the latter switchclosing a circuit from transformer I20, through the stop button andcontacts H of press limit switch LS1, to energize coil I28 which closesreversing switches R connecting power lines L1, L2 and L3 with motor 26,to hold the same in reverse only long enough to operate side arms I? towiden thegap between the mold sections I3 and I 5, substantially asillustrated in Figure 4. This gap is immediately narrowed to theoriginal closed positions of the mold sections (Figure 8) by operationtimercam C4 to close switch S4, thereby closing a circuit fromtransformer I20 through the "stop button, contacts ab of press limitswitch LS1 (which momentarily closed when the press motor wasmomentarily reversed), to energize coil I2I to start motor 26. Cam C4will open switch S4 simultaneously with said opening of contacts (0-2).The motor, of course, is stopped again when the press is closed by limitswitch LS1 opening contacts a-b.

This aforementioned partial opening and closing of the press may betermed a bumping action, which is efiective to force from between themold sections the gases generated from certain pigments in hard rubberor similar plastic compositions used in the manufacture of steeringwheels or the like. These gases are prevented from permeating the airabout the press by being drawn into the chamber I l in head I4 andcarried away through exhaust conduit M by the suction means (not shown).

' After said bumping operation timer cam C5 may be operable to closecontacts (1-6 of a switch S5. to energize a solenoid 54 in a circuitthrough press closed contacts a-c and the 7 stop button, and therebyoperate valve 5| (Figure 8) to supply pressure fluid from pressureoilsupply piping 52, through piping'bfil to the rams 35. This urges piston35 upwardly to apply heavy hydraulic force between the upper and lowermold sections i3 and i and thereby form the article W, as best shown inFigures 1 and 5, under the influence of continuous vulcanizing heatconducted to the mold sections from the heating plates 32 and 3?.movement of the press is efiective to preheat and soften the rubber ofthe green article W, while the ram applies the requisite high pressureto the mold sections for forming the article. The nature of the rams aresuch that the respective lower mold sections will be moved intoself-centering firm engagement with their upper mold sections. Thisself-centering action particularly is made possible by the provision ofthe oil recovery system in the cylinder 39, as previously described.

At the end of the curing cycle cam C5 opens contacts 01-6 and closescontacts d-f of switch S5 (Figure 14) to (fie-energize coil 54 andenergize coil 53 in the same circuit. This operates valve 5i to returnthe pressure oil from rams 36, to

the source of supply, through piping 5B and return piping 57, therebycausing pistons to lower. When the hydraulic pressure is thus releasedcam C5 moves switch S5 to the inoperative position thereof.

Simultaneously with or subsequent to full release of the hydraulicpressure, timer cam C3 momentarily closes switch S3 to energize coilH255 to start motor 25 in reverse as before, at the same time closing apress motor holding switch HR in a press opening circuit, through presslimit switch LS2 and normally closed timer switch S2, to keep coil I23energized and hence keep the motor 25 operating in reverse until saidmotor is The initial closing stopped in the fully open position of thepress,

by cam I25 on large driven gear 23 operating limit switch LS2 (Figure2). After the press has reached the fully open position shown in Figure8 the timer motor T will be stopped by cam C1 opening switch S1 and thevarious parts of the electrical circuit will be set as shown in Figure14 for a succeeding curing cycle as described above.

The press may be stopped at any point during the opening or closing ofthe same, by pressing the stop button (Figure 14) to open the primarycircuit connected to the transformer I20,

thereby de-energizing either coil 12] or coil I23- to stop press motor26. The press may be reversed while closing by pressing an open buttonin a circuit between the press-closing holding circuit and press-openingholding circuit.

Upon the press operating to the fully open position shown in Figure 8the cam rollers on the driven gears 23 and 23 will have urged therespective sets of cam arms 9! and arms 88 to the raised positionsthereof, arms 9| and88 being latched together by the latching device 92.Raising arm 88 shifts rods 85 and 82 upwardly to engage the ends ofprongs 83 with the core 0 of wheel W, thereby projecting the latterupwardly to a position where it is readily removable from the lower moldsection (see chain-dotted position of wheel W in Figure 8) Once thefinished article is removed the operator may operate a switch (notshown) momentarily to energize coil H9 (Figures 3 to 11) and therebyrelease latch'end $8 from the catch or sleeve 99 of cam arm 99. Thispermits arm 88 to drop by gravity and thereby permit rod 82 also to dropby gravity to Withdraw the prongs 33 thereof so that the operator mayfreely place another preformed article W in the lower mold cavity forthe next succeeding curing cycle of the press, arms 88 and 9! beingmechanically latched together upon relatively moving into'latchingalignment with each other (Figure 12) when the press is again closed.

Thus has been briefiy described a vulcanizing press which is capable ofeffectively and efiiciently accomplishing the stated objects of theinvention. Modifications of the invention may be resorted to withoutdeparting from the spirit thereof or the scope of the appended claims.

What is claimed is:

1. An article-forming press of the class described comprising arelatively fixed mold member and a relatively movable mold member forregistry therewith, power means for movingsaid movable member toward andfrom registry with said fixed member, article ejecting means inassociation with said fixed mold member, a first element shiftabletooperate said ejecting means for ejecting an article, a second elementadapted to shift with said first element and independently thereof,releasable means for locking said first and second elements togetherwhen closing the mold to be shiftable as a unit, means operable by saidpower means during opening of the mold to shift said second element andthrough said locking means to shift said first element to operate saidejecting means for stripping an article from said fixed mold member, andmeans operable at will to release said locking means and thereby rendersaid ejecting means inoperative.

2. An article-forming press of the class described ccmprising arelatively fixed mold member and a relatively movable mold member forregistry therewith, power means for moving said -movable member towardand from registry with said fixed member, article ejecting means inassociation with said fixed mold member, a first element shiftable tooperate said ejecting means for jecting an article, a second elementadapted to shift with said first element and independently thereof,releasable means for locking said first and second elements togetherwhen closing the mold to be shiftable as a unit, means operable by saidpower means during opening of the mold to shift said second element andthrough said locking means to shift said first element to operate saidejecting means for stripping an article from said fixed mold member, andmeans operable at will to release said locking means and thereby rendersaid ejecting means inoperative, said locking means comprising aspring-pressed latch on one of said elements and a recessed portion onthe other element for receiving said latch, said latch and recessedportion having cooperating guide surfaces whereby said latch will beautomatically guided into said recessed portion when said elements arerelatively moved into association with each other upon closing the mold.

HENNING T. TORNBERG,

